There are four places to be won, through four play-off paths each containing four teams with one-legged semi-finals and finals.
The draw takes place at 12:00 GMT on Thursday, which will create the individual paths.
In the semi-finals, the seeded teams will be at home:
Pot 1 v Pot 4
Pot 2 v Pot 3
Each of the four paths will have one team from each pot, feeding into a final.
The home advantage in each of the finals will be determined by the draw on Thursday.
The draw starts with Pot 1 and ends with Pot 4.
The semi-finals will take place on Thursday, 26 March at 17:00 GMT or 19:45 GMT, and the finals on Tuesday, 31 March with kick-off times of 17:00 BST or 19:45 BST.
So is being in Pot 1 more favourable than Pot 2? It does not make too much difference apart from being kept away from the other Pot 1 teams in the paths.
While Pot 4 has teams who failed to make the top two of their World Cup groups, there are nations within it who will have a higher world ranking than some in Pot 3.
The other argument is the teams in Pot 3 have better recent form, so should be seen as stronger opponents.
What’s most important is being in Pot 1 or Pot 2, and guaranteeing a home semi-final.